I'm looking for a volunteer---someone who has already bought the 10th edition of the textbook, or will do so shortly---who will meet me weekly, or bi-weekly, or however often problem sets are posted, so we can compare problem numbers between the 10th edition and the 9th edition (which I already have).

If I am able to get a volunteer, I will post corresponding problem numbers in this thread after each time we meet. This way, other students who already have the 9th edition, or can obtain it much more cheaply than the 10th, won't have to buy another edition of the textbook just so they can do the problems.

I'm sure people would give you karma for it (which means bonus marks apparently)

I wouldn't mind helping, though I haven't bought the book yet. Also, I don't think it'll need to be a weekly thing. I think all the assigned questions have already been posted, and there aren't any evaluated problem sets, just suggested practice problems.

I wouldn't mind helping, though I haven't bought the book yet. Also, I don't think it'll need to be a weekly thing. I think all the assigned questions have already been posted, and there aren't any evaluated problem sets, just suggested practice problems.

I'll private message you to set up meeting times?

Yan

Some problems could be added (I will mark them by a special colour) so it is not one time thing but not every week either

Let me clarify this issue once and for all. Officially you use 10th edition. Neither 9th, nor 8th, etc.

Content however is only marginally different. Main issue here is home assignments. Usually publishers when preparing new edition shuffle problems like card sharpers to discourage of usage of the old edition because they want bigger sales. In this case there are some discrepancies, not very significant. Therefore using older edition you can add up with solving the wrong problem.

However you do not submit home assignments, they are not graded at all, but you are given quizzes drawn from the problems in the home assignments. So if you solved the right problem, you would solve during the quiz exactly same problem. If you solved the wrong problem, you would solve during the quiz similar problem, which makes a difference.

Yes, we posted online required problems for sections 1.1-2.2, but it was done only because textbook has not arrived to bookstore yet, so we were dealing with a problem of not our making. However it is time consuming. Creation of comparison table is also time consuming and error prone. So, you should not expect instructors to be involved in this. if there are volunteers--go ahead! (IMHO, if there are two independent pairs it would be more reliable).

PS. I have no idea how much the textbooks authors profit. AFAIK none of them is on the Forbes list.

I wouldn't mind helping, though I haven't bought the book yet. Also, I don't think it'll need to be a weekly thing. I think all the assigned questions have already been posted, and there aren't any evaluated problem sets, just suggested practice problems.

I've noticed for almost all the questions so far, the 10th edition and the 9th edition are identical in the questions, no "shuffling" has taken place. However I only checked the assigned questions up to chapter 2.2

Yanyuan and I compared problem numbers in chapters 1 through 4 today. We found that:

Most questions and question numbers are identical.

A few question numbers are different. Yanyuan will post these shortly.

There are some minor stylistic differences, such as writing equations in the form $$M(x,y) + N(x,y)y' = 0$$ instead of $$M(x,y)\, dx + N(x,y)\, dy = 0$$

There is one problem whose text was actually changed between the two editions. In section 2.3, problem 12 in the 10th edition is similar to problem 11 in the 9th edition. The 9th edition reads:

Quote from: 9th edition

11. A recent college graduate borrows $100,000 at an interest rate of 9% to purchase a condominium.Anticipating steady salary increases, the buyer expects to make payments at amonthly rate of 800(1 + t/120), where t is the number of months since the loan was made.(a) Assuming that this payment schedule can be maintained, when will the loan be fullypaid?(b) Assuming the same payment schedule, how large a loan could be paid off in exactly20 years?

The 10th reads:

Quote from: 10th edition

12. A recent college graduate borrows $150,000 at an interest rate of 6% to purchase a condominium.Anticipating steady salary increases, the buyer expects to make payments at amonthly rate of 800 + 10t, where t is the number of months since the loan was made.(a) Assuming that this payment schedule can be maintained, when will the loan be fullypaid?(b) Assuming the same payment schedule, how large a loan could be paid off in exactly20 years?